We introduce two scalar leptoquarks, the SU(2) L isosinglet denoted φ ∼ (3, 1, −1/3) and the isotriplet ϕ ∼ (3, 3, −1/3), to explain observed deviations from the standard model in semi-leptonic B-meson decays. We explore the regions of parameter space in which this model accommodates the persistent tensions in the decay observables R D ( * ) , R K ( * ) , and angular observables in b → sµµ transitions. Additionally, we exploit the role of these exotics in existing models for one-loop neutrino mass generation derived from ∆L = 2 effective operators. Introducing the vector-like quark χ ∼ (3, 2, −5/6) necessary for lepton-number violation, we consider the contribution of both leptoquarks to the generation of radiative neutrino mass. We find that constraints permit simultaneously accommodating the flavour anomalies while also explaining the relative smallness of neutrino mass without the need for cancellation between leptoquark contributions. A characteristic prediction of our model is a rate of muon-electron conversion in nuclei fixed by the anomalies in b → sµµ and neutrino mass; the COMET experiment will thus test and potentially falsify our scenario. The model also predicts signatures that will be tested at the LHC and Belle II.

We identify the two scalar leptoquarks capable of generating sign-dependent contributions to leptonic magnetic moments, R 2 ∼ ð3; 2; 7=6Þ and S 1 ∼ ð3; 1; −1=3Þ, as favored by current measurements. We consider the case in which the electron and muon sectors are decoupled, and real-valued Yukawa couplings are specified using an up-type quark mass-diagonal basis. Contributions to Δa e arise from charmcontaining loops and Δa μ from top-containing loops-hence avoiding dangerous LFV constraints, particularly from μ → eγ. The strongest constraints on these models arise from contributions to the Z leptonic decay widths, high-p T leptonic tails at the LHC, and from (semi)leptonic kaon decays. To be a comprehensive solution to the ðg − 2Þ e=μ puzzle we find that the mass of either leptoquark must be ≲65 TeV. This analysis can be embedded within broader flavor anomaly studies, including those of hierarchical leptoquark coupling structures. It can also be straightforwardly adapted to accommodate future measurements of leptonic magnetic moments, such as those expected from the Muon g − 2 collaboration in the near future.

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